<template>
  <div>
    <span>全选:</span>
    <input type="checkbox" v-model= "isAll"/>
    <button @click="btn">反选</button>
    <ul>
      <li v-for="item in arr"  :key="item.name">
        <input type="checkbox" v-model= "item.c"/>
        <span >{{item.name}}</span>
      </li>
    </ul>
  </div>
</template>

<script>
export default {
  data() {
    return {
      arr: [
        {
          name: "猪八戒",
          c: false,
        },
        {
          name: "孙悟空",
          c: false,
        },
        {
          name: "唐僧",
          c: false,
        },
        {
          name: "白龙马",
          c: false,
        },
      ],
    };
  },
  methods: {
     btn() {
      return this.arr.forEach(item => item.c = !item.c)
     }
    
  },
  computed: {
    isAll: {
      get() {
        return this.arr.every(item => {
          return item.c === true
        })
      },
      set(value) {
        console.log(value); 
        this.arr.forEach(item => item.c = value)
      }
    }

  }
};
</script>

<style>
</style>